[Osteoid osteoma in the hip of 12-year-old girl].

Osteoid osteoma is a benign skeletal tumour most commonly located in the cortex of long bones and easily diagnosed with distinct symptoms and radiographic appearance. The less common peri-articular location presents a diagnostic difficulty due to its non-specific symptoms and the absence of radiological findings in the early state. This often leads to a delay in the final diagnosis and treatment. A case review of a young girl diagnosed with periarticular osteoid osteoma of the acetabulum is reported.